Locking and unlocking mechanism

ABSTRACT

A locking and unlocking mechanism to secure a door has four control positions of the controlling mechanism. Two positions of the control mechanism place the securing mechanism in a deadlock condition. Direct operational links connect the control mechanism with the securing mechanism.

United States Patent [1 1 1111 3,837,117 Butt Se t. 24 1974 LOCKING ANDUNLOCKING MECHANISM 3,009,545 11/1961 Young 49/16 x 3,017,967 1/1962 Ad1 49 18 [75] Invent Gerald Independence 3,082,847 3/1963 Yofiii g 49i16[73] Assignee: Stewart-Decatur Security Syst 3,271,901 9/1918 Bednar49/18 X Incorporated, Covington, Ky. Primary Examiner-Dennis L. Taylor[22] Filed 1972 Attorney, Agent, or Firm-John G. Schenk [21] Appl. No.:303,240

[57] ABSTRACT (g1. A locking and unlocking mechanism to secure a door[58] Fie'ld 49/15 20 has four control positions of the controllingmechanism. Two positions of the control mechanism place [56] ReferencesCited the securing mechanism in a deadlock condition. Di-

rect operational links connect the control mechanism UNITED STATESPATENTS with the securing mechanism. 1,030,699 6/1912 Youngblood 49/17 12,899,027 8/1959 Adam 49/16 20 Claims, 11 Drawing Figures i O a a o 1112g; '9' 55 a? 25 29 27 28 1 7 60 4| 6 1 D c 6 42 26 3s 59 35 1 I f j I l4 i 56 3o 32 57 l I I +-44 97 5e 53 i J1 i W FMH U r45 E:l IIIIIIIPATENTEDSEPZMHH SHEET 3 BF 4 fL gbz FIG] FIG.6

1 LOCKING AND UNLOCKING MECHANISM BACKGROUND OF THE INVENTION Thisinvention relates generally to prison cell door mechanisms andinoreparticularly to a locking and unlocking apparatus for sliding celldoors.

Numerous locking devices are known in the art for securing a single celldoor as well as a plurality of doors such as an entire cell block. Thesedevices include the simple key lock mechanism as well as sophisticatedmechanisms which not only unlock the cell door but open the door aswell. The prior art mechanisms have not been entirely satisfactory as isevident from the numerous reports of prisoners escaping from secured orlocked jail cells. The known locking mechanisms for jail cells have notheretofore incorporated a manual deadlock to prevent convict tamperingand opening the cells after the cells have been secured.

Accordingly, it is an object of this invention to provide a locking andunlocking mechanism for sliding cell doors having a manual deadlockcondition to prevent unauthorized opening of the cell door.

A further object of this invention is to provide a locking and unlockingmechanism for sliding cell doors of simple aria economical constfiictfinand which eliminate numerous linkages and slot members previously usedin such devices.

A still further object of this invention is to provide a locking andunlocking mechanism for sliding cell doors having four control positionseach independent of the other positions.

Yet another object of this invention is to provide a locking andunlocking mechanism for sliding cell doors having two separate deadlockconditions.

SUMMARY OF THE INVENTION This invention provides an improved locking andunlocking mechanism for sliding cell doors. The control mechanism hasfour control positions which dictate the movement ofthe securingmechanism, i.e., whether the door may be locked or unlocked. Directlinks connect the control mechanism with the securing mechanism. Twopositions of the control mechanism provide deadlock conditions for thesecuring mechanism. The electric control positions includes a deadlockto prevent manual opening of the locking mechanism thereby insuring thatonly an electrical signal will cause the securing mechanism to becomeunlocked. A key position in the control mechanism only permits manualunlocking of the securing mechanism. A fourth or release position of thecontrol mechanism provides automatic unlocking of the securing mechanismin the event of a power failure or the like.

Other objects, details, uses and advantages of this invention willbecome apparent as the following description of an exemplary embodimentthereof presented in the accompanying drawings proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings show apresent exem-- LII LII

FIG. 4 is a sectional view of the mechanism taken along line 4-4 of FIG.3;

FIG. 5 is a diagrammatic representation ofthe master bar cam member andthe respective positions of the roller member relative to the controlpositions;

FIG. 6 is an enlarged elevation view of the control panel particularlyshowing the actuator bar;

FIG. 7 is a sectional view of the control panel taken along line 7-7 ofFIG. 6;

FIG. 8 is an enlarged elevation view of the mechanism used to unlock thesecuring mechanism in the key position;

FIG. 9 is an enlarged sectional view taken along line 99 of FIG. 1;

FIG. 10 is a sectional view taken along line 10-10 of FIG. 8; and

FIG. 11 is an electrical schematic showing the electrical control of thelocking and unlocking mechanism.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Reference is now made to FIG.1 of the drawings which illustrates one exemplary embodiment of theimproved locking and unlocking mechanism for sliding cell doors. Forillustrative purposes only, the mechanism of this invention is shown inconjunction with a single cell door 20. It is readily apparent that themechanism can also be used to control a plurality of cell doors. Themechanism of this invention comprises a securing mechanism operativelyconnected with a control mechanism each of which is designated generallyby the reference numerals 21 and 22, respectively.

The cell door is carried for sliding movement along a transom 23 by apair of wheels 24 and 25 as, S seen in FIGS. 1, 3 and 4. The wheels 24and 25 roll along a track 26 which is securedly fixed to the transom byany suitable means such as welding or the like. A

hanger bar 27 is carried on one side of the wheels 24 and 25. Bolts 28and 29 respectively protrude through the hanger bar 27 and wheels 24 and25 project into a travel rail 34 on the opposite side of the wheels.Suitable washers or the like provide separation between the wheels andthe hanger bar and travel rail to insure that the wheels will be freerolling.

The cell door 20 is fixedly secured to a hanger angle member 30 by anysuitable means such as welding or the like. The hanger angle 20 isconnected to the hanger bar 27 by a fixed pivot bolt 31 and a pairofeccentric bushings and bolts designated generally as 32 and 33. Theeccentrics and bolts 32 and 33 permit adjustment of the hanger angleabout'the bolt 31 to insure a level travel of the cell door 20 betweenthe open and closed position.

Mounted at each end of the track 26 is an adjustable stop member 35,each having a cushion engaging surface 36 of rubber or the like. Eachstop member 35 is positioned so that the engaging surface 36 will engagethe respective ends of the hanger bar 27 when the cell door 20 is ateither the full open or closed position. The stop members 35 areadjustable to permit limited axial adjustmentofthe engaging surface 36to insure that the cell door 20 is properly positioned in the full openor closed condition.

A suitable U-bracket or the like 37 supports a door kicker arm 40 forengagement with one end of the hanger bar 27. The arm 40 is biased tothe right by a spring 41 as seen in FIG. 1. When the cell door 20 is inthe closed position, the hanger rail 27 urges the arm 40 to the leftagainst the force of the spring 41 such that the arm 40 is essentiallycocked when the door is closed. The door 20 is prevented from moving tothe open position by the cooperative engagement of a cut out portion orchannel 39 at one end of the travel rail 34 with a hearing or roller 42.The roller 42 is secured to a lock or drop bar 44 by a suitable screw orthe like 43. When the drop bar 44 is raised upwardly, as will beexplained hereinbelow, the roller 42 is raised out of the cut outportion 39. This removes the restraining force of the hanger bar 27against the arm 40 allowing the spring 41 to urge the arm 40 to theright as seen in FIG. 1. The cell door 20 is only moved a short distanceduring which the roller 42 rolls along the top surface 38 of the travelrail 34. The door 20 may be opened to the full open position duringwhich the roller 42 will be carried by the surface 38 of the travel rail34. To close the cell door 20, the door is manually urged to the left asseen in FIG. 1 with sufficient force to overcome the spring 41 and untilthe roller 42 once again drops in the cut out portion 39 of the travelrail 34. When this occurs, the drop bar 44 moves downward to lock thedoor 20 in the closed position.

The drop bar 44 is carried for sliding movement therein in a lock post45 at one edge of the door 20. The lock post 45 includes front and rearcover plates 46 and 47 as seen in FIG. 2. The plates 46 and 47 arejoined together by suitable means such as screws, bolts or the like soas to completely enclose the drop bar 44. A guide member 50 is mountedin inverted position (FIG. 2) along the lower edge of the cell frameworkto provide a guide for the door 20. The guide member 50 is formed with aslot therein through which the drop bar 44 passes. A door guide 51 issecured by suitable means such as welding'to the lower edge of the celldoor 20. The guide 51 is shaped in a complementary form as the guide 50such that one wall portion of the door guide 51 travels within thechannel defined by the guide member 50. The door guide 51 is providedwith a slot 52 through which the drop bar 44 will pass when the door 20is in the closed position. With the drop bar 44 passing through the slotin the guides 50 and 51, the door 20 may not be opened and is thus in asecured condition. The door 20 may only be opened after the drop bar 44has been moved vertically a sufficient distance to clear the slot in thedoor guide 51.

In the closed position, the cell door 20 has one edge 53 whichcooperates with a strike member 54. The other end of the door 20 restsin front of the lock post 45.

A casing bar partially shown in FIG. 1 at 55 is connected to the casinglock bar lever 58 that is pivotally mounted in a control panel 60 by apivot member 59. The casing lock bar lever 58 is shown in the lockedposition. The casing bar 55 and lock bar lever 58 operate in awell-known manner and need not be described herein. Retainer straps 56and 57 are connected to hanger bar 27 for the prevention of lifting door20 off the track 26.

The structure and operation of the securing mechanism 21 is best seen byreferring to FIGS. 3 and 4. The drop bar 44 is operatively connectedwith a drop bar extension 61. One end of the drop bar extension 61 isformed with a slot in which the drop bar 44 fits. The screw 43 extendsthrough an aperture in the drop bar extension 61 to engage the drop bar44 to operatively connect the two members thereby. A spacer or washer 62insures that the roller 42 is positioned to engage the travel rail 34.The drop bar extension 61 is pivotally supported at the other end by abell crank 63 which is rotationally mounted to the transom 23 by a pivotelement 64. One end of the bell crank 63 is connected in pivotingfashion to the bolt 66. The bolt 66 further serves to secure the dropbar extension roller to the drop bar extension 61. It can be observedthat rotation of the bell crank 63 counterclockwise about the pivot 64will cause the drop bar extension 61 to be raised in a verticaldirection thereby lifting the dropbar 44 when the control mechanism 22is in the proper position as will be explained hereinbelow. A pair ofbearings 67 are secured to the transom 23 on either side of the drop barextension 61 to insure proper tracking in the vertical direction of thedrop bar extension 61 during locking and unlocking of the cell door 20.

A pendulum 70 having a protruding mass 71 at one end is pivotallysecured to the drop bar extension 61 by a pivot 72. The pendulum 70 willhave a natural gravitational force acting to return the pendulum to thevertical position due to the large mass 71 at the lower end. However, toprovide a positive return to vertical, a spring 73 is connected to theupper end of the pendulum 70. The spring 73 thus provides a positivereturn to vertical for the pendulum 70. To prevent overtravel of thependulum 70 in the counterclockwise direction, a protrusion or stopperflange 74 is provided on the drop bar extension 61. Thus, pendulum 70abuts against the stopper 74 in the vertical position.

In the control position illustrated in FIG. 3, which is the electricalcontrol position, the drop bar extension 61 is prevented from upwardmovement because of engagement of the upper end of pendulum 70 with aone ofa pair of tube segments 75. The tube segments 75 are carried on acam plate 76. The cam plate 76 is rotationally driven by a shaded polegear motor designated generally as 77. Such gear motors are commerciallyavailable from Dayton Electric Manufacturing Co. of Chicago, Ill., andneed not be described herein. When energy is applied to the motor 77,the cam plate 76 will start to rotate in the counterclockwise directionas viewed in FIG. 3. Rotation of the cam plate 76 in thecounterclockwise direction will cause the tube segments 75 to urgependulum 70 in a clockwise direction and at the same time disengage themotor limit switch 80. Continued rotation of the cam plate 76 will bringthe camming surface of one hemisphere into contact with the roller 65.Since the pendulum 70 has become disengaged from the tube segment 75continued rota tion of the cam plate 76 will urge the roller member 65in the upward direction thereby raising the drop bar extension 61 anddrop bar 44. When the roller 42 has been raised above the surface 38 ofthe travel rail 34, the kicker arm 40 (FIG. 1) will urge the cell door20 open as hereinabove described. When the cam plate 76 has madeone-half revolution, the camming surface will once again engage themotor limit switch 80 thereby cutting the power to the motor. The gearmotor 77 is supported by a motor mount bracket 81 which is fixedlysecured to the transom 23 by bolts or the like 82. In the electriccondition as shown in FIG. 3, it is seen that the drop bar 44 may not bemanually raised due to the engagement of the tube segment 75 with thependulum 70. Thus, the electric control condition is seen to be in adeadlock position. Only an electrical signal applied to the gear motor77 will permit unlocking of the cell door 20.

Referring again to FIG. 1, the control mechanism 22 is mounted in acontrol panel 60. The control panel 60 is secured at the end of the lineof cells. The control panel shown in FIG. 1 has the front cover 83 (FIG.7) removed and a portion of the inner panel 84 broken away. The controlmechanism 22 has four positions or conditions designated as A, B. C andD. The positions indicate respectively deadlock, electric, key andrelease.

A handle or lever 85 is used to move the control mechanism from oneposition to another position. A spring biased shaft 87 is mounted at oneend of the handle 85 within a knob 86. The shaft 87 is urged outwardlyto cooperatively engage detents 90, 91, 92 and 93 which are secured tothe inner panel 84. The handle 85 is operatively connected to a spurgear 94 by a shaft 95. The spur gear 94 drives a rack 96 which forms oneend of an actuator bar 97. It can be seen in FIG. 6 that movement of thehandle (shown in phantom) from one position to another position willcause the actuator bar to be raised or lowered. In FIG. 6, the handle isin the release condition so that a protrusion or lug 79 formed on theactuator bar engages a stop member 99. The stop members 98 and 99 arefixedly secured to the rear wall of the control panel 60. Each of thestop members is adjustable to permit precise travel adjustment of thebar 97. Due to the stop members 98 and 99, the handle 85 may only berotated in the counterclockwise direction when starting from the releasedetent 93 and clockwise from the deadlock detent 90.

The upper end of the actuator bar 97 (FIG. 1) is pivotally connected toa bell crank 100 through link 101. The bell crank 100 is pivotallysecured to the transom 23 by a bell crank bracket 102. The bell crank100 is pivotally connected to a master bar 103 through a link 104. Themaster bar 103 is supported for sliding movement along the transom 23 bybrackets 105 and 106. Each bracket 105 and 106 includes a pair ofbearings 107 (FIG. 3) on either side of the master bar 103 to permitrelatively frictionless travel of the bar 103. The brackets 105 and 106support the master bar 103 a sufficient horizontal distance away fromthe transom 23 such that a master bar cam 108, as seen in FIGS. 3-5,will engage the roller 65. The cam 108 is rigidly connected with themaster bar by any suitable means such as welding, and moves therewith.It can be seen that the relative position of the roller 65 to the masterbar cam 108 will be changed as the handle 85 is moved from one controlposition to another because of the connecting links 101 and 104 and thebell crank 100.

The relative positioning between the roller 65 and cam 108 is best seenin FIG. wherein the roller 65 is shown in solid lines in the electricposition. The remaining three control positions are shown and the rollerin each position is shown in phantom lines.

The cam 108 is seen to be formed with an inclined surface 109, asubstantially U-shaped end 110 and an upwardly projecting portion 111extending from one leg of the U-shaped portion 110. In the deadlockcontrol position, the master bar 103 will have been urged to its extremeright hand position. In this position, the roller 65 will be cradledwithin the U-shaped portion 110 of the cam 108. With the roller 65 socradled, the drop bar extension 61 may not be raised in the verticaldirection. Thus, the drop bar 44 may not be manually raised nor wouldenergization of the gear motor 77 permit raising of the drop barextension. Thus, the cell doors 20 are secured and there is no way tounlock such doors until the handle 85 has been moved from its deadlockcontrol position. Rotation of the handle 85 from the deadlock detent 90to the electric detent 91 will urge the master bar 103 to the left tothat position shown in FIG. 3 wherein the drop bar extension 61 may beraised as hereinabove described.

Movement of the handle 85 from the electric detent 91 to the key detent92 will urge the cam 108 to the left relative to the roller to thatposition wherein the roller 65 is at the bottom of the inclined portion109. In addition, the inclined surface 113 of a pendulum tripper 112(FIG. 3) will have engaged the pendulum mass 71 causing the pendulum torotate in a clockwise direction. This movement will free the upper endof the pendulum 70 from the tube segment so that the drop bar extension61 can be raised by a counterclockwise rotation of bell crank 63 as willbe explained hereinbelow. The pendulum tripper 112 is secured by weldingor the like to the master bar 103 and is carried therewith.

As the handle is moved from the key detent 92 to the release detent 93,the cam 108 is urged to the left thereby driving the roller 65 up theinclined surface 109 to the release position as shown in FIG. 5. Therelative movement of the roller 65 along the surface 109 results in adirect lifting of the drop bar extension 61 thereby raising the roller42 out of the channel 39 of the travel rail 34. Thus, when the controlhandle 85 is moved to the release detent 93, the drop bar 44 isautomatically raised such that the cell doors 20 are unlocked ashereinabove described. It should be noted that the handle 85 may not bemoved to the deadlock detent while the drop bar extension 61 is in theraised position, i.e., any cell door 20 is not locked. In the unlockedcondition of any cell door 20, the roller 42 will be resting on thesurface 38 of travel rail 34. In addition, the roller 65 will be raiseda corresponding distance. In the raised position, the projecting end 111will engage the raised roller 65 to prevent the handle 85 from moving tothe full deadlock position.

When the handle 85 is moved to the key detent 92, the securing mechanism21 is positioned so that counterclockwise rotation of bell crank 63(FIG. 3) will raise the drop bar extension 61 and drop bar 44 to unlockthe cell door 20. At each cell door a key pilaster 114 (FIG. 1) ismounted. The bell crank 63 is rotated through operation of the door 115.As best seen in FIGS. 8-10, the door 115 is pivotally connected to thepilaster front wall 116 by a suitable hinge member 117. A lock mechanism118 is mounted in the door and is operable by a key. The lock 118 onlyserves to secure the door 115 relative to the wall 116. The lock 118 inno way operates to unlock the cell door 20. A bracket 119 is secured byany suitable means to the inside surface of the door 115. It should benoted that the front wall 116 and door 115 have been removed in FIG. 8.A rod 120 having a substantially right angle turn at one end projectsthrough a cooperating aperture in the bracket 119. Suitable means suchas a lock washer, C- ring, or the like 132 is attached to the rod 120 toprevent its inadvertent removal from the bracket 119. The upper end ofthe rod 120 is pivotally attached to a bell crank 121 as seen in FIG. 1.The bell crank 121 is pivotally attached to the transom 23 by pivot 122.Link 123 pivotally connects the bell crank 121 with a link arm 125 whichis pivotally connected with the bell crank 63. Link arm 125 has limitedaxial movement due to coaction of link arm elongated slot 124 and bolt124a mounted in transom 23. Accordingly, when the door 115 is openedthrough a 90 arc, the rod 120 is urged upward causing the bell crank 121to rotate about pivot 122 in the clockwise direction. Clockwise movementof the bell crank 121 will cause a movementof the link arm 125 to theleft as viewed in FIGS. 1 and 3. The movement of the link arm 125 causesthe bell crank 63 to be rotated in a counterclockwise direction aboutthe pivot 64 to lift the roller 65 and drop bar extension 61 ashereinabove described.

Referring once again to FIG. 10, a latch member link 126 is pivotallyattached through a pivot pin 127 to a lug 128, the lug 128 being securedby any suitable means to the door 115. The latch member link 126 isformed with a slot 129 therealong through which a pin 130 is engaged.The pin 130 is fixedly connected to the strike 54. When the door 115 isopened, the latch member link 126 pivots about pin 127 and permits thedoor 115 to be opened until the pin 130 reaches the notched end 131 ofthe slot 129. To prevent inadvertent closing of the door 115, the latchmember link 126 must be lifted to take the pin 130 out of the notchedend 131.

The electrical opening of the cell door is performed through a controlconsole 133 shown schematically in the circuit diagram of FIG. 11. Theconsole 133 may be positioned adjacent the control panel 60 or placed ata remote location. A master power switch 134 interrupts the power from apower supply 135 to the electrical circuit. A second interrupted switch136 is mounted in the control panel 60 and opened and closed by theactuator bar 97 as seen in FIG. 6. In FIG. 6, it is seen that theactuator bar 97 is formed with a groove 137. In any position of theactuator bar except when the groove 137 is in alignment with theinterrupter switch 136 plunger 138, the switch 136 will be in the opencondition thereby preventing power from being supplied to the gear motor77. Accordingly, before the gear motor 77 can be actuated, switches 134and 136 must be closed.

Referring once again to FIG. 11, a cell switch 139 must be closed inorder to actuate the gear motor 77. If there is a plurality of cellsinvolved, individual isolation switches shown generally as 140 may beused to isolate any cell which it is not desired to open. It can be seenthat the switch 80 is in the open condition due to engagement of thecam'plate 76 with the switch 80 plunger 88 (FIG. 3). To unlock the celldoor 20, a push button 141 is closed. The closing of the push button 141completes the circuit from the power supply 135 through lead line 142,switch 134, fuse 143, switches 136, 139, 141, lead line 144 and leadline 145 to the gear motor 77. Lead line 146 completes the circuit fromthe gear motor 77 back to the power supply 135. After the gear motor 77had been energized and cam plate 76 rotated to disengage the plunger 88,the switch 80 is closed such that power to the gear motor 77 is suppliedover lead line 144a, through switch 80 the lead line 145. At thecompletion of onehalf revolution of the cam plate 76, the plunger 88 isagain engaged so that switch 80 is opened to interrupt the power to thegear motor 77.

A suitable indicator light 147 is mounted at the control console 133 toprovide an indication of the safe or unsafe condition of the cell door20. Power is supplied to the indicator light 147 through lead line 148and resistor 149. The resistor 149 reduces the voltage of the powersupply to the proper amount needed for the light 147. It may be notedthat if a plurality of cells is involved, a transformer would replacethe resistor 149. An indicator switch 150 is mounted on the transom 23as best seen in FIG. 3. A projecting protuberance 151 on the drop barextension 61 opens and closes the switch 150. When the drop barextension 61 is in the down or locked position, the indicator switch 150is closed thereby completing the circuit through the light 147. Thus,when the cell door 20 is locked and in the safed condition, the light147 will be lit. When the drop bar extension 61 is raised, theprotuberance 151 is disengaged from the indicator switch plunger 152 andthe switch 150 is opened thereby breaking the circuit for the light 147.Thus the light is not illuminated wherein the unsafe condition isindicated.

While a present exemplary embodiment of this invention has beenillustrated and described, it will be recognized that this invention maybe otherwise variously embodied and practiced within the scope of thefollowing claims.

What is claimed is:

1. A mechanism for locking and unlocking a door comprising:

a bar being positionable relative to the door to provide locking andunlocking conditions;

securing means operatively connected with said bar to move said bar fromthe locked condition to the unlocked condition;

control means having four operating control positions, two of thecontrol positions resulting in a positional deadlock for sad bar andsecuring means; and

link means operatively connecting said control means with said securingwherein movement of said bar to the unlocked condition is dependent onthe operating position of said control means whereby positioning saidcontrol means in each of two operating positions operatively places saidbar and securing mechanism in a deadlock position to prevent manualmovement of said bar to the unlocked condition.

2. The mechanism as set forth in claim 1 further comprising travel meansoperatively carried by the door and movable therewith, said travel meanspreventing opening of the door in the locked condition and holding saidbar in the unlocked condition when the door is open.

3. The mechanism as set forth in claim 1 in which movement of saidcontrol means to a first positional deadlock control position moves saidlink means to co operatively engage and deadlock said securing means toprevent said securing means from moving said bar to the unlockedcondition; and further comprising electric drive means operativelyconnected with said securing means to permit electrode drive operationof said securing means to move said bar to the unlocked condition whensaid control means is in the second positonal deadlock control position;and switch means responsive to said control means to prevent actuationof said electric drive means in any control position except the secondcontrol position.

4. The mechanism as set forth in claim 3 further comprisinghand-operated link means connected with said securing means to permitmanual operation of said securing means when said control means is in athird control position wherein actuation of said hand-operated linkmeans causes said securing means to move said bar to the unlockedcondition.

5. The mechanism as set forth in claim 4 in which movement of saidcontrol means to a fourth control position simultaneously causes saidsecuring means to move said bar to the unlocked condition.

6. The mechanism as set forth in claim 1 in which said securing meansfurther comprises a bar extension member operatively connected at oneend with said bar, said bar being moved in response to movement of saidbar extension member, a roller rotatably mounted adjacent the other endof said extension member, said roller coacting with said link means inresponse to movement of said control means.

7. The mechanism as set forth in claim 6 in which said link meanscomprise a master bar mounted for movement normal to said bar extensionmember, said master bar being connected with said control means, andfurther comprising a cam fixedly secured to said master bar, said camcoacting with said roller wherein relative movement occurs therebetweenin response to movement of said control means.

8. The mechanism as set forth in claim 7 in which said cam includes asubstantially U-shaped end portion and an inclined portion.

9. The mechanism as set forth in claim 8 in which movement of saidcontrol means to a first control position moves said master bar relativeto said roller to relatively position said roller in the U-shapedportion of said cam to positionally deadlock said bar extension frommoving said bar to the unlocked condition.

10. The mechanism as set forth in claim 9 in which movement of saidcontrol means to a second control position moves said master barrelative to said roller to position said roller out of said U-shapedportion and further comprising electric drive means operativelyconnected with said bar extension to move said bar extension uponactuation of said drive means and switch means responsive to saidcontrol means to prevent actuation of said drive means when said controlmeans is in any control position except the second control position.

11. The mechanism as set forth in claim 10 further comprisinghand-operated link means connected with said bar extension roller formovement of said bar extension member when said control means is in athird control position wherein actuation of said handoperated link meanscauses said bar extension member to move said bar to the unlockedcondition.

12. The mechanism as set forth in claim 11 in which movement of saidcontrol means to a fourth control position moves said master barrelative to said bar extension member to drive said roller up said caminclined portion thereby moving said bar to the unlocked condition.

13. The mechanism as set forth in claim 12 in which said electric drivemeans includes an electric motor, a cam plate rotationally driven bysaid motor, said cam plate engaging said roller to cam said rollerduring part of the rotational movement of said cam plate, and furthercomprising a limit switch responsive to said cam plate for interruptingoperation of said motor when said bar has moved to the unlockedcondition.

14. The mechanism as set forth in claim 13 further comprising a pendulumpivotally mounted at its center portion on said bar extension member,and in which said cam plate includes a pendulum engaging segment whereina deadlock condition exists during engagement of said cam plate segmentswith said pendulum.

15. The mechanism as set forth in claim 14 further comprising a tripperarm secured tosaid master bar, said arm being engageable with saidpendulum to pivot said pendulum out of engagement with said cam platesegment during movement of said control means to the third and fourthcontrol positions.

16. The mechanism as set forth in claim 15 further comprising a rollerrotationally secured to said bar, a travel rail carried by the door andmovable therewith, said rail having a bar roller receiving portion toreceive said bar roller in the bar locked condition and wherein said barroller engages the top surface of said rail in rolling contact in thebar unlocked condition.

17. The mechanism as set forth in claim 16 in which said control meanscomprises a handle moveable to the four control positions, an actuatorbar, gear means operatively connecting said handle with said actuatorbar wherein movement of said handle to a control position causes amovement of said actuator arm, and wherein said actuator bar ispivotally connected with said master bar whereby movement of saidactuator arm causes relative movement between said master bar and barextension roller.

18. The mechanism as set forth in claim 17 in which said actuator bar isformed with a groove thereon, said groove cooperating with said switchmeans when said handle is in the second control position therebyallowing said switch to close to permit actuation of said electricmotor.

19. The mechanism as set forth in claim 18 in which said hand-operatedlink means comprises a pivotally mounted door, a rod connected with saiddoor, a link arm operatively connected with said rod at one end, apivotally mounted bell crank connecting the other end of said link armwith said bar extension roller wherein pivotal movement of said doorcauses movement of said bar extension roller to move said bar to theunlocked condition.

20. The mechanism as set forth in claim 19 further comprising a doorguide secured to the door and movable therewith, said guide being formedwith a bar receiving slot therein for receipt of said bar in the lockedcondition.

1. A mechanism for locking and unlocking a door comprising: a bar beingpositionable relative to the door to provide locking and unlockingconditions; securing means operatively connected with said bar to movesaid bar from the locked condition to the unlocked condition; controlmeans having four operating control positions, two of the controlpositions resulting in a positional deadlock for sad bar and securingmeans; and link means operatively connecting said control means withsaid securing wherein movement of said bar to the unlocked condition isdependent on the operating position of said control means wherebypositioning said control means in each of two operating positionsoperatively places said bar and securing mechanism in a deadlockposition to prevent manual movement of said bar to the unlockedcondition.
 2. The mechanism as set forth in claim 1 further comprisingtravel means operatively carried by the door and movable therewith, saidtravel means preventing opening of the door in the locked condition andholding said bar in the unlocked condition when the door is open.
 3. Themechanism as set forth in claim 1 in which movement of said controlmeans to a first positional deadlock control position moves said linkmeans to cooperatively engage and deadlock said securing means toprevent said securing means from moving said bar to the unlockedcondition; and further comprising electric drive means operativelyconnected with said securing means to permit electrode drive operationof said securing means to move said bar to the unlocked condition whensaid control means is in the second positonal deadlock control position;and switch means responsive to said control means to prevent actuationof said electric drive means in any control position except the secondcontrol position.
 4. The mechanism as set forth in claim 3 furthercomprising hand-operated link means connected with said securing meansto permit manual operation of said securing means when said controlmeans is in a third control position wherein actuation of saidhand-operated link means causes said securing means to move said bar tothe unlocked condition.
 5. The mechanism as set forth in claim 4 inwhich movement of said control means to a fourth control positionsimultaneously causes said securing means to move said bar to theunlocked condition.
 6. The mechanism as set forth in claim 1 in whichsaid securing means further comprises a bar extension member operativelyconnected at one end with said bar, said bar being moved in response tomovement of said bar extension member, a roller rotatably mountedadjacent the other end of said extension member, said roller coactingwith said link means in response to movement of said control means. 7.The mechanism as set forth in claim 6 in which said link means comprisea master bar mounted for movement normal to said bar extension member,said master bar being connected with said control means, and furthercomprising a cam fixedly secured to said master bar, said cam coactingwith said roller wherein relative movement occurs therebetween inresponse to movement of said control means.
 8. The mechanism as setforth in claim 7 in which said cam includes a substantially U-shaped endportion and an inclined portion.
 9. The mechanism as set forth in claim8 in which movement of said control means to a first control positionmoves said master bar relative to said roller to relatively positionsaid roller in the U-shaped portion of said cam to positionally deadlocksaid bar extension from moving said bar to the unlocked condition. 10.The mechanism as set forth in claim 9 in which movement of said controlmeans to a second control position moves said master bar relative tosaid roller to position said roller out of said U-shaped portion andfurther comprising electric drive means operatively connected with saidbar extension to move said bar extension upon actuation of said drivemeans and switch means responsive to said control means to preventactuation of said drive means when said control means is in any controlposition except the second control position.
 11. The mechanism as setforth in claim 10 further comprising hand-operated link means connectedwith said bar extension roller for movement of said bar extension memberwhen said control means is in a third control position wherein actuationof said hand-operated link means causes said bar extension member tomove said bar to the unlocked condition.
 12. The mechanism as set forthin claim 11 in which movement of said control means to a fourth controlposition moves said master bar relative to said bar extension member todrive said roller up said cam inclined portion thereby moving said barto the unlocked condition.
 13. The mechanism as set forth in claim 12 inwhich said electric drive means includes an electric motor, a cam platerotationally driven by said motor, said cam plate engaging said rollerto cam said roller during part of the rotational movement of said camplate, and further comprising a limit switch responsive to said camplate for interrupting operation of said motor when said bar has movedto the unlocked condition.
 14. The mechanism as set forth in claim 13further comprising a pendulum pivotally mounted at its center portion onsaid bar extension member, and in which said cam plate includes apendulum engaging segment wherein a deadlock condition exists duringengagement of said cam plate segments with said pendulum.
 15. Themechanism as set forth in claim 14 further comprising a tripper armsecured to said master bar, said arm being engageable with said pendulumto pivot said pendulum out of engagement with said cam plate segmentduring movement of said control means to the third and fourth controlpositions.
 16. The mechanism as set forth in claim 15 further comprisinga roller rotationally secured to said bar, a travel rail carried by thedoor and movable therewith, said rail having a bar roller receivingportion to receive said bar roller in the bar locked condition andwherein said bar roller engages the top surface of said rail in rollingcontact in the bar unlocked condition.
 17. The mechanism as set forth inclaim 16 in which said control means comprises a handle moveable to thefour control positions, an actuator bar, gear means operativelyconnecting said handle with said actuator bar wherein movement of saidhandle to a control position causes a movement of said actuator arm, andwherein said actuator bar is pivotally connected with said master barwhereby movement of said actuator arm causes relative movement betweensaid master bar and bar extension roller.
 18. The mechanism as set forthin claim 17 in which said actuator bar is formed with a groove thereon,said groove cooperating with said switch means when said handle is inthe second control position thereby allowing said switch to close topermit actuation of said electric motor.
 19. The mechanism as set forthin claim 18 in which said hand-operated link means comprises a pivotallymounted door, a rod connected with said door, a link arm operativelyconnected with said rod at one end, a pivotally mounted bell crankconnecting the other end of said link arm with said bar extension rollerwherein pivotal movement of said door causes movement of said barextension roller to move said bar to the unlocked condition.
 20. Themechanism as set forth in claim 19 further comprising a door guidesecured to the door and movable therewith, said guide being formed witha bar receiving slot therein for receipt of said bar in the lockedcondition.